Refrigerator



Nov. 8, 1938. R. H. STARR Z REFRIGERATOR Filed Feb. 20, 1935 INVENTOR Fay/7200a /7. Sfarr I r, W 0/ 0 ATTORNEY Patented Nov. 8, 1938 UNITED STATES PATIENT OFFlCE 2,136,222 REFRIGERATOR Raymond H. Starr, Kansas City, Mo. Application February 20, 1935, Serial No. 2,363

Claims.

This invention relates to refrigerators and particularly to those of that character wherein condensation from therefrigerating elements is caught by drip pans that are supported over the merchandise undergoing refrigeration. Inrefrigerators of this character, the drip pans not only interfere with circulation of air around the refrigerating elements, but they form surfaces on which moisture in the air condenses and drips therefrom onto the merchandise.

It is, therefore, the principal object of the present invention to provide a refrigerating element and drip pan construction which promotes circulation of air and prevents condensation on the under surface of the pan.

In accomplishing this and other objects of the invention, as hereinafter pointed out, I have providedimproved details of structure, the preferred form of which is illustrated in the accompanying 20 drawing, wherein:-

Fig. 1 is a cross sectional view through adisplay type refrigerator equipped with refrigerating elements and drip pans embodying the features of the present invention.

Fig. 2 is an enlarged cross section through one of the refrigerating elements and the drip pan associated therewith.

Fig. 3 is a detail perspective view of one end of the refrigerating elements particularly illustrating their relation to the drip pans which 30 collect water resulting from defrosting of the refrigerating elements.

Fig. 4 is a fragmentary vertical section through one of the refrigerating elements and drip pans supported thereunder.

Fig. 5 is an enlarged perspective view of a portion of one of the drip pans particularly illustrating. its construction whereby condensation in the bottom of the. pan is prevented.

Referring more in detail to the drawing:

l designates a conventional refrigerator display caseincluding front and rear walls 2 and 3 connected by top and bottom walls 4 and 5 and end walls 6 to form a longitudinal refrigerating compartment I. Supported in the refrigerating compartment is a plurality of superimposed shelves 8 and 8 upon which merchandise is placed for display through transparent panels 9 that are incorporated into the front wall 3. Access is had r to the display on the shelves through openings l0 provided in the rear wall 2 and closed by doors I I. In display refrigerators of this character, refrigerating elements I! are usually located in the top of the compartment 1 and over the merchandise on display in order to provide natural gravitational movement of the cold air downwardly. from the relatively cold temperature surrounding the refrigerating elements'and over the relatively warmer merchandise on the shelves and to movement of relatively warm air surrounding the merchandise upwardly for circulation around the refrigerating elements.

It is well known that moisturecontent of the merchandise on display is absorbed. by the air and deposited on the refrigerating elements in the form of frost which .is added to by accumulations caused by moisture laden air being car This construction takes care of the moisture from the refrigerating elementsbut due to the size and relatively lowconductivity of the pans, they tend to retain low temperatures and are'slow to conform to air temperatures within the case. Consequently, air contacting the under surface of the pans reaches the dew point and, therefore, condenses thereon and drips onto the merchandise. I

I, therefore, provide an arrangement of refrigerating elements whereby the areas from which the melting ice drips are limited to a small portion of the refrigerating surfaces. The sizev of the drip pans can thus be reduced to that sufficient to catch the water, thereby not only promoting circulation of air about the refrigerating elements but reducing the thermal capacity of the pan so that the temperature of the pan is quicker to respond to the temperature of the air.

Consequently, the air does not as quickly reach the dew point when moving in contact with the pan.

Opposite facesof the pan have different capacities for absorbing radiant energy; that face which faces the refrigerating element is bright, while the other face is darkened. Thus the temperature of the pan itself will be warmer than if both faces have equal capacities for absorbing radiant energy.

In thefillustrated instance, the refrigerating elements l2 are arranged in pairs designated I3 and I4 and extend longitudinally of the compartment, each element comprising interconnected pipes l5 arranged in the form of a hollow square with its diagonal axes in perpendicular and horizontal planes so that the radiating fins l6 thereon are positioned with the lower corners II thereof located in the perpendicular plane. By thus locating the fins, moisture melting from the pipes gravitates downwardly over the faces of the fins and along the lower converging edges l8 and I9 thereof to the corners II, from where it drips into the drip pans above mentioned.

With this arrangement of the coils, it is clearly obvious that a drip pan need be provided of only sufficient width to catch the water dripping from the corners II.

In order to insure that the water does not drip from the edges l8 and i9, the fins are preferably spaced close enough upon the pipes so that the capillary action afforded by the spaces.

therebetween is sufiicient to retain the flowing water in contact therewith until it reaches the points H.

The drip pans 20 and 2| for the respective refrigerating sections are formed in the shape of troughs sloping from one end of the compartment to the other where they empty into a collection pan 22 having an opening 23 in one corner thereof connected with a waste pipe 24 leading to a sewer or other place of disposal.

For convenience of construction, the troughs 20 and 2| are preferably formed of strips of sheet metal bent on their longitudinal centers to provide valleys 25 and upwardly diverging sides 26 and 2! spaced apart a sufficient distance to assure collection of the water dripping from the fins H.

In order to stiffen the troughs and enhance the appearance of the upper edges thereof, they are preferably flanged inwardly and then downwardly to lie against the inner faces of the troughs as indicated at 2B. The pan 22 is also constructed of sheet metal and has flaring sides 29 conforming to the side flanges of the troughs as best illustrated in Fig. 3.

In order to further reduce the thermal capacity of the troughs and pan 22, they are preferably constructed of a metal having high thermal conductivity such as for example aluminium or an aluminium alloy of extremely light gauge.

By thus constructing the pans, the high thermal conductivity thereof causes the temperature of the pans to more quickly assume the temperature of the air circulating thereunder and substantially relieves the fins of condensation on the under surfaces thereof. I have found, however, that by treating the under surfaces of the pans with a dark coating having heat absorbing properties as indicated at 30, the metal quickly absorbs and retains heat radiated from the merchandise on display so that the temperature of the pan tends to approach that of the merchandise.

I have also found that by providing the pan with a bright or polished upper surface, as indicated at 3|, the radiant energy absorbing capacity thereof is greatly reduced and radiation of the heat absorbed through the lower heat absorbing face is inhibited in the direction of the cooling coil, the temperature of the coil, therefore, has less effect on the pan, and I am enabled to additionally raise the temperature thereof.

The troughs are preferably supported under the respective cooling elements by means of hooks 32 engaging the lowermost pipe l5 and having their lower ends connected to cross bars 33 extending transversely of the troughs in spaced relation to the bottom thereof.

For example, assuming that the temperature surrounding the coils which may be termed a cold body is 30 and the merchandise which may be termed a warm body is maintained at a temperature of 40 the temperature of the drip pan can be maintained at a constant temperature of 38 which is more nearly that of the merchandise and is high enough to prevent air moving thereover from reaching the dew point. The maintenance of this temperature also has the advantage in that it prevents formation of ice in the pans that would cause them to overfiow when the refrigerating elements are defrosted.

It is also possible to maintain the pans in relatively dry condition because the water does not freeze therein, but readily drains therefrom into the collecting pan and from there into the disposal pipe 24.

,The drip pans also provide means for controlling air circulation about the cooling elements. For example, when warm merchandise is placed on the shelves, heat radiating therefrom is absorbed by the coating 30 to raise the temperature of the pans to approximately that of the merchandise. Upon heating of the pans, the air circulating thereabout becomes warmer and results in increased circulation about the cooling elements. As the merchandise cools off, the heat radiation therefrom decreases and the pans cool off in the same proportion to correspondingly reduce air circulation about the cooling coils.

From the foregoing it is apparent that I have provided a coil arrangement and pan construction which prevents condensation on the under side of the pan that ordinarily drips upon the merchandise on display.

By maintaining the pan at a temperature substantially that of the air moving thereacross, the pan is maintained in relatively dry and sanitary condition.

It is also obvious that since the pan is only of suflicient width to catch the moisture dripping from the coils, it does not interfere with circulation about the refrigerating elements, but due to the high temperature thereof, the circulation about the cooling elements is increased.

What I claim and desire to secure by Letters Patent is:

1. In a refrigerator, a cooling element having a row of drip portions for ice melted from said element, and a drip pan supported under said drip portions and having a polished inner surface facing said cooling element.

2. In a refrigerator, a cooling element having a row of drip portions for ice melted from said cooling element, and a drip pan supported under said drip portions and having a polished inner surface facing said cooling element and having a dark, heat absorbing outer surface.

3. In a refrigerator, a cooling element having a row of drip portions for ice melted from said cooling element, and a drip pan supported under said drip portions and having a polished surface facing said cooling element and a heat absorbing surface on the side opposite said cooling element.

4. In a refrigerator, a cooling element in the refrigerator, and a drip pan supported under said elementand having polished surfaces facing said coolingelement and heat absorbing surfaces on the other sides thereof.

5. In a refrigerator having a merchandise storage space, a cooling element for effecting circulation of air in said storage space, and a shield member interposed between said storage space and the cooling element and having a heat absorbing surface facing said storage space for absorbing heat radiating from merchandise contained in said space and having apolished surface facing the cooling element for retaining the heat absorbed by the heat absorbing surface.

RAYMOND H. STARR. 

